MSD anti-obesity drug ‘fails to achieve statistical significance’

New trial data for MK-0557, an investigational anti-obesity treatment made by Merck Sharp & Dohme (MSD), failed to provide “clinically meaningful weight loss” in a long-term trial.

Researchers involved in the studies, which were part of a ten-year research programme, have concluded that the drug is not a “useful weapon” against obesity, although they reserve the possibility that MK-0557 could prove to be of use as part of a combination therapy.

The drug is designed to target the neuropeptide Y (NPY) receptor, which has been identified as an appetite stimulant. However, its single mechanism of action may not be enough to make it an effective anti-obesity treatment on its own, according Steven Heymsfield of MSD, who was part of the research team.

He remarked: “When you hit this receptor as a single target, it doesn’t generally appear to change energy balance profoundly.”

“However, other chronic diseases, such as high blood pressure or diabetes, commonly require two or even three drugs to achieve optimal therapeutic response,” the scientist added.

The report concluded by saying that single-target drugs like MK-0557 might work best as part of a combination therapy, whereby they work in conjunction to create a “synergistic effect”.

Current anti-obesity treatments include Xenical, the GlaxoSmithKline drug marketed by Roche in the UK, and Acomplia, the Sanofi-Aventis drug launched in the UK in late June.